Lythos, or Lithos, (known in Roman mythology as Lapis, or Lapys) is one of the five fictional Titans that Hades sets free in Hercules. He appears to be a large two-headed boulder creature with red eyes. The inside of his mouth is red as well. Since he is very large and heavy, Lythos has the ability to stomp on the ground and cause massive earthquakes.
He is defeated when Hercules uses Stratos to suck him up along with the other two Titans and then flings him and the others into outer space.
His name could be refering to the greek word "lithos", which means "stone".